There are no singing nymphs and naiads wandering around—Philippe Rahm seems to have cornered the market on those—but the Penezic & Rogina project in the Arsenale has an echo of Italo Calvino’s invisible city of Armilla, whose only form is tubs and toilets and copper pipes, and whose citizens are the aforementioned maidens. The P & R installation actually kicks it up a notch, and takes in the digital and mechanical systems of a typical house as well, but as far as we know, there aren’t any nymphs in the future, which is a shame, so we allowed ourselves a moment to look back.